Bar code inventory systems are known in the art. These systems process bar code data that are affixed to different types of objects, such as product packages. The bar code data includes a set of vertical lines of varying widths. A bar code inventory system includes a bar code reader, such as a light pen or scan gun, that transforms the vertical lines (printed bars and spaces between them) of the bar code label into a set of digital high and low pulses of varying duration, corresponding to the varying widths of the vertical lines of the bar code label.
Known stationary bar code inventory systems include an interface device, also often called a bar code wedge in the industry, that is connected between the bar code reader and a computer. The bar code wedge is typically tethered to the bar code reader by a flexible electrical cord. This allows an individual to move the bar code reader to any position within the range of the flexible cord. The information obtained from the bar code reader is transmitted through the flexible electrical cord to the bar code wedge. The bar code wedge transforms the information into a character set, such as ASCII, that may be processed by a computer. Connection between the bar code wedge and the computer may be accomplished through a serial port of the computer or through a keyboard input port.
A shortcoming of prior art bar code inventory systems is that they are not readily portable. That is, the computer and bar code wedge of the system mitigate against portable operation of the system. Some portability is afforded by the bar code reader being attached to the wedge with a flexible electrical cord. However, the length of such a cord has practical limits. For example, if one is using a bar code inventory system in a warehouse, a long flexible electrical cord may create a hazard for individuals working in the warehouse. In addition, a long flexible electrical cord will also be susceptible to damage from equipment, such as fork lifts, operating in the warehouse.
Consequently, it would be highly desirable to provide a bar code inventory system that is not positionally constrained by a physically tethered bar code reader. Such a system would preferably provide instantaneous communication between a bar code reader and a base computer. In such a configuration, the bar code reader could rely upon immediate feedback from the base computer and therefore operate as a tethered bar code reader. Ideally, such a system would operate with existing bar code inventory systems and thereby not necessitate the costly replacement of one bar code inventory system for another.